This specification relates to identifying a query language for some or all of the search terms in a search query.
Search engines allow users to find documents (e.g., web pages) using text queries. Each query typically includes one or more search terms that the user selects. A search engine uses the term or terms in the query to present potentially relevant documents to the user.
In order to provide the best results for a query, the search engine can augment the user's query with variants of some query terms to improve recall and precision. For example, if a user submitted the term “job,” the search engine can augment it by adding the term “jobs” to the search. Similarly, if a user submitted the term “car,” the search engine can augment it by adding the term “automobile” to the search.
The way in which queries are augmented is generally language dependent. For example, while “automobile” is synonymous with “car” in English, it is not in French, where “car” means “because.” In addition, diacritical expansions (e.g., Zunrich to Zurich and Zuerich) that can be used to augment a query are also generally language dependent.